 |
 |
| Alternating current - | Back-and-forth movement of electrons in a wire. AC Voltages can be transformed to higher or lower voltages. High voltages are used to send electricity over long distances from the power station and can be reduced to a safer voltage for use in the house. |
|
| ANSI - | American National Standards Institute, Inc. The coordinator of standards, including lighting standards, on a national level. It is composed of trade organizations, technical societies, professional groups, consumer organizations, as well as company members. |
|
| Arc Lamp - | A discharge lamp in which the light is emitted by an arc discharge or by its electrodes. (HID) |
|
| Arc Tube - | A tube within the outer glass envelope of an HID lamp and made of clear quartz or ceramic that contains the arc stream. |
|
| Average Rated Life - | How long it takes to burn out a lamp. For example, you can expect a 60-watt bulb to burn for about 1000 hours, based on continuous testing of lamps in laboratories. The 1000-hour rating is the point in time when 50% of the tested samples have burned out and 50% still shine. |
|
| Ballast - | A device used with an electric discharge lamp to obtain and regulate the necessary electric current. |
|
| Base - | The portion of the lamp that provides a means of connecting the lamp to the socket. |
|
| Beam Candlepower - | A measurement of beam intensity from reflector lamps as opposed to overall lumens of non-reflector lamps. |
|
| Beam Spread - | The angle of light distribution from a specific light source on one plane in which the candlepower is 50% of the maximum. |
|
| Brightness - | The intensity of the sensation, which results from viewing a surface or space which directs light into the eyes. |
|
| Burn Cycle - | The burning hours per start of a lighting system. Burn cycle affects the average rated lamp life. Fluorescent lamp life is rated at 3 hours per burn cycle. For fluorescent systems that have longer burn cycles, the lamps will have longer than average rated life; for fluorescent systems that have shorter burn cycles, the lamps will have shorter than average rated life. |
|
| Candela - | The international basic physical quantity of all measurements of light. All other units are derived from it. Its value is determined by the light emitted by a laboratory device operating at a specific temperature. |
|
| Candlepower - | A measurement of light intensity. |
|
| Cathode - | An electrode that emits electrons. The fluorescent lamp cathode emits or discharges electrons to the cathode at the opposite end of the lamp. |
|
| Chromaticity (of a color)- | The dominant or complementary wavelength and purity aspects of the color taken together (of a light source) - the whiteness of a light source expressed in degrees Kelvin (K). |
|
| Color Rendering Index (CRI) - | A rating method by which any fluorescent is evaluated according to its variance from natural outdoor light which has a CRI of 100. It is sometimes referred to as Chromatic Index. |
|
| Compact Fluorescent Lamp (CFL) - | The generic name for a family of single-ended fluorescent lamps of folded or bridged tube design with high color rendering and long life. |
|
| Correlated Color Temperature (CCT) - | The absolute temperature, measured in degrees Kelvin, of a blackbody radiator whose chromaticity most nearly resembles that of the light source. |
|
| Canadian Standards Association (CSA) - | An organization that writes standards and tests lighting equipment for performance as well as electrical and fire safety. Many products sold for consumer use in Canada must have CSA or equivalent approval (CUL). |
|
| Dichroic - | Dichroic is usually a term associated with MR-16 and MR-11 lamps. It describes the coating on the inside of these lamps. The coating is put on in multiple layers and serves to reflect certain wavelengths of visible light. |
|
| Direct Current - | Electric current without alterations. DC does not affect incandescent adversely. High voltage Mercury Vapor can be used if DC is used with polarity switches. |
|
| Efficacy - | A measure used to compare light output to energy consumption. Efficacy is measured in lumens per watt. For example, if a 100-watt light source produces 1750 lumens, then the efficacy of the light source is 17.5 lumens per watt. |
|
| Electric Discharge Lamps - | A lamp in which light is produced by the passage of an electric current through a vapor or gas. |
|
| Electrode - | A coated metal element that facilitates the emission of electrons to form an arc within a fluorescent lamp. |
|
| Energy Policy Act (EPACT) - | Energy legislation passed by the U.S. Congress in 1992. The lighting portion includes lamp labeling and minimum energy efficacy (lumens/watt) requirements for many incandescent and fluorescent lamp types. |
|
| ENERGY STAR® - | E S® was introduced by the U.S. Environmental Protection Agency in 1992 as a voluntary labeling program designed to identify and promote energy-efficient products that reduce carbon dioxide emissions. The EPA partnered with the U.S. Department of Energy in 1996 to promote the ENERGY STAR® label. |
|
| Filament - | A tungsten wire that incandesces or lights up when an electric current runs through it. The light source in an incandescent lamp. |
|
| Fluorescent Lamps - | A low-pressure mercury electric-discharge lamp in which a phosphor transforms some of the UV energy generated by the discharge into light. |
|
| Foot Candle - | One lumen uniformly distributed over one square foot of surface. One lumen falling on one square foot of surface produces illumination of one- foot candle. |
|
| Halogen - | A gas-filled tungsten incandescent lamp, containing a certain proportion of halogen in an inert gas that is under pressure. |
|
| High-Intensity Discharge Lamp (HID) - | A general term for mercury vapor, metal halide and high-pressure sodium lamps. HID lamps contain compact arc tubes that enclose various gases and metal salts operating at relatively high pressures and temperatures. |
|
| High Output - | A fluorescent lamp designed for use with an 800-milliampere ballast. Will usually operate at low temperatures near zero and still produce high light output. |
|
| High Voltage - | Voltage of 208 and higher. |
|
| High Power Factor (HPF) - | The term applied to lighting ballasts and other AC electrical devices that measure 0.9 (90%) or higher. |
|
| High-Pressure Sodium Lamp (HPS) - | HPS lamps are high intensity discharge lamps which produce light by an electrical discharge through sodium vapor operating at relatively high pressures and temperatures. |
|
| Incandescence - | Light emission by a heated filament or coil. |
|
| Incandescent Lamp - | A lamp in which light is produced by the passage of an electric current through a wire. |
|
| Infrared - | Radiant energy heat with wavelengths that are longer than the wavelengths of the visible spectrum. |
|
| Instant Start - | Refers to fluorescent lamps that start instantly, without pre-heating of cathodes, and without the need of starters. |
|
| Kelvin Temperature Scale - | Absolute temperature scale, 0º Kelvin is equal to
-273.16º Centigrade. Term used to indicate the comparative color appearance of a light source compared to a theoretical black body. |
|
| Kilowatt Hour - | One thousand watts of electric energy consumed in one hour. Example: One 1,000-watt lamp or ten 100-watt lamps burning for one hour. |
|
| Krypton - | A very heavy inert gas which permits the filament to glow hotter and brighter while still providing long life. |
|
| Lamp (light bulb) - | Generic term for man-made light source. |
|
| Lumen - | The SI unit of luminous flux. Lumens represent the time rate of transferring luminous energy; quantity of light. One lumen is the light flux falling on a surface of one square foot, every part of which is one foot from a point source having a luminous intensity of one candela in all directions. |
|
| Metal Halide Lamp - | A high intensity discharge lamp in which the light is produced by the radiation from mercury together with halides of metals such as sodium and scandium. |
|
| Mercury Vapor Lamp - | An electric discharge lamp in which the major portion of the radiation is produced by the excitation of mercury atoms. |
|
| M.O.L. - | Maximum overall length of a lamp. |
|
| Nominal Length - | Overall length of a fluorescent lamp installed (including sockets). |
|
| Preheat - | A fluorescent system that requires starters. This system requires several seconds of heating from the time the circuit is turned on to the time the lamp produces light. |
|
| Rapid Start - | A fluorescent system that does not require starters and takes 1 or 2 seconds to light. |
|
| Starter - | A device used in conjunction with a ballast for the purpose of starting an electric discharge lamp. |
|
| Spectral - | Color spectrum rating. |
|
| Total Harmonic Distortion (THD) - | A measure of the degree to which the input current is distorted from a sine wave, measured as a percentage. THD is usually expressed as a percentage of the fundamental frequency line current. THD for 4-foot electromagnetic fluorescent ballasts range from 20% to 40%. For compact fluorescent ballasts, THD levels greater than 50% are common. |
|
| Underwriters Laboratories (UL) - | A private organization that tests and lists electrical and fire safety according to recognized UL and other standards. |
|
| Ultraviolet Radiation - | For practical purposes, any radiant energy within the wavelength range of 10 to 380 nanometers. It is invisible radiation that is shorter in wavelength than visible violet light (literally beyond the violet light). UV is emitted when the outer jacket of some HID lamps is broken. |
|
| Volt - | The standard unit of measurement for electrical potential. |
|
| Voltage - | The difference in electrical potential between two points of an electrical circuit. The voltage of a circuit is the electrical pressure it gives. In an incandescent lamp, "voltage" designates the supply voltage to which the lamp should be connected. In other lamp types, it may refer to "operating voltage" of a lighted discharge lamp. |
|
| Watt - | A unit of power consumption. |
|
|
